Gas burner assemblies used for producing fire effects in fountains, ponds, and other water features typically deliver a combustible gas, such natural gas or propane, to one or more nozzles or frits disposed beneath the surface of the water. Such burner assemblies may be match-lit or may include an electronic ignition module. Electronic ignition modules provide a pilot gas nozzle and an ignition source, such as a glow plug or hot wire igniter, disposed above the surface of the water, and operate during start-up in order to ignite first the pilot, then gas emerging from the water via the submerged nozzles or fits. Assemblies also commonly include a thermocouple, thermopile, or other sensor that senses when the burner assembly has been ignited. The output of the sensor is used to stop the flow of gas if the burner assembly blows out or otherwise becomes extinguished, and also may be used to control operation of the pilot gas nozzle and ignition source in any electronic ignition module (to provide an intermittent or interrupted pilot light feature). The burner assembly may include one or more mesh screens which surround the pilot gas nozzle, sensor, and other components to mechanically protect those components. Systems known to the applicant require a minimum gas supply pressure of at least 2.0 psig, which is an elevated delivery pressure in comparison to the 6-14 inch water column (0.25-0.5 psig) gas pressures commonly employed as “standard pressure” in residential (in-home) gas distribution.
Existing gas burner assemblies appear to rely upon high gas supply pressures and high nozzle outputs to both push fuel through the submerged nozzles or fits and maintain a flame in outdoor conditions. Notably, ANSI standard Z21.97 and corresponding CSA standard 2.41 require that systems with flame sensors light and remain burning in a 10 mph horizontal breeze. But such gas supply pressure requirements are frequently incompatible with existing residential gas supplies, which although optionally upgradable to 2.0 psig service at the service entry/gas meter would also require the installation of in-line pressure regulators for each of the residence's “standard pressure”-rated appliances. Finally, common residential gas distribution piping may cause substantial pressure losses at the gas flow rates required to supply a high BTU, remotely located device such as patio or in-yard installed fire-on-water feature, requiring the replacement of existing small diameter piping, the installation of new or replacement large diameter piping, and careful evaluation of the number of piping elbows and bends necessary to reach the desired feature location.